The present invention relates to photographic printers. In particular, the present invention is a system which provides signals indicative of the direction of movement of filters which adjust the color content of print light in order to facilitate quick changeover from one setup to another setup.
Photographic printers produce color or black and white prints of transparencies from photographic film originals (generally negatives). High intensity light is passed through the film and imaged on the photosensitive print medium (film or paper). The photographic emulsion layers on the print paper or film are exposed and subsequently processed to produce a print or transparency of the scene contained in the film original.
In most photographic printers, the color content of the print light is adjusted by means of movable dichroic filters. Color balancing procedures are used to properly position or select filters so that the printing light has the proper spectral content. In general, each "setup" for a different film/paper combination requires a different color balance. As a result, each time the operator of the printer changes from one setup to another, the color balance and the position of the movable filters must be changed. The changeover has normally been achieved by recording the desired dichroic filter dial positions and then resetting the dials to those numbers each time the particular setup is used.